MSU Affiliations: Neuroscience Program, Center for Integrative Toxicology (CIT), Department of Chemical Engineering and Materials Science, Department of Pharmacology and Toxicology, and Fraunhofer Center for Coatings and Laser Applications
Research Synopsis
Our research is at the crossroads of physical/analytical electrochemistry and materials science. The overall goal of much of our work is to develop advanced carbon electrode materials with well controlled structure-function relationships for use in bioanalysis, as platforms for chemical and biological sensing, and energy storage and conversion. Boron-doped microcrystalline and ultrananocrystalline diamond thin films, tetrahedral amorphous carbon (ta-C) thin films, diamond-coated nanoscopic powders and sp2-sp3 composite powders are electrode materials under study. These materials are synthesized in the laboratory by chemical vapor deposition and laser-arc deposition methods, characterized and utilized in various electrochemical applications. Generally speaking, diamond and ta-C electrodes offer significant improvements over commonly used sp2 carbon electrodes in terms of (i) detection figures of merit in electroanalytical measurements, and (ii) dimensional stability and corrosion resistance. We seek to understand how the physical, chemical and electronic properties of these materials affect their electrochemical performance.
Current core research projects in the group include:
- Optically transparent diamond and diamond-like carbon thin-film electrodes for chemical analysis using transmission spectroelectrochemical methods (UV/Vis and IR). Platforms are being developed for chemical and biological analyte sensing that allow for both electrochemical and optical detection.
- Fundamental studies are being conducted with the boron-doped diamond and ta-C electrodes to better understand how the electrolyte composition (aqueous electrolytes and room temperature ionic liquids) affects the heterogeneous electron-transfer kinetics for various inner and outer-sphere redox analytes. Scanning electrochemical microscopy (SECM) is a tool being used to investigate the spatial nature of the electrochemical activity of these carbon materials.
- The surfaces of boron-doped diamond and ta-C electrodes are being chemically modified in controlled ways to learn if selective recognition of bioanalytes can be achieved and if surface interactions with redox analytes can be promoted, which might improve the detection figures of merit. Flow injection analysis and HPLC with electrochemical detection are tools being used in this work.
- Dimensionally stable diamond anodes are being developed for the electrochemical remediation of pollutants in water supplies. Diamond and ta-C electrodes are also being researched for water quality monitoring.
- High surface area and electrically conducting diamond powders are being developed and evaluated for use as (i) a corrosion-resistant electrocatalyst support in PEM fuel cells, (ii) an electrode for electrochemical double layer capacitors, and (iii) a stationary phase for electrochemically-modulated liquid chromatography.
- Investigation of the formation and corrosion protection afforded by trichromium process (TCP) and non-chromium conversion coatings on aerospace metal alloys.
- Carbon fiber and diamond microelectrodes and diamond microelectrode arrays are being used to study neurogenic (norepinephrine, ATP and adenosine) control of vascular tone and how these control mechanisms are impaired in salt-sensitive and obesity-related hypertension. Studies utilize human tissues and tissues from various animal models.
- Diamond microelectrodes and microelectrode arrays are being used to study serotonergic (5-HT) and nitrergic (NO) signaling in the small and large intestine and how these control mechanisms are impaired in obesity. Studies utilize human tissues and tissues from various animal models.
